Office of Water (4606) EPA 816-F-09-011 October 2009 

The Environmental Protection Agency (EPA) published the final National Primary Drinking 

Water Regulations (NPDWRs) for Aircraft Public Water Systems under the Safe Drinking 

Water Act (SDWA) on October 19, 2009. Aircraft public water systems are subject to the 

requirements of SDWA and the NPDWRs. 

Why did EPA issue the Aircraft Drinking Water Rule (ADWR)? 

The primary purpose of the Aircraft Drinking Water Rule (ADWR) is to ensure that safe and 

reliable drinking water is provided to aircraft passengers and crew. This entails providing air 

carriers with a feasible way to comply with SDWA and the NPDWRs. The existing 

NPDWRs were designed for traditional, stationary public water systems (PWSs), not mobile 

aircraft water systems that are operationally very different. Aircraft must maintain rigorous 

operating schedules. They fly to multiple destinations throughout the course of any given day 

and may board drinking water from sources at any of these destinations. Aircraft board water 

from airport watering points via temporary connections. Aircraft drinking water safety 

depends on a number of factors including the quality of the water that is boarded from these 

multiple sources, the care used to board the water, and the operation and maintenance of the 

onboard water system and the water transfer equipment (such as water cabinets, trucks, carts, 

and hoses). These unique operational characteristics present different challenges that 

necessitate tailoring the NPDWRs for aircraft PWSs in the final ADWR. 

What concerns does the ADWR address? 

In 2004, EPA found all aircraft PWSs to be out of compliance with the NPDWRs. According 

to the air carriers, it is not feasible for them to comply with all of the monitoring that is 

required in the existing regulations. Subsequently, EPA tested 327 aircraft of which 15 

percent tested positive for total coliform. EPA considers this to be a high percentage of 

positive samples. In response to these findings, EPA embarked on an accelerated process to 

tailor the existing regulations for aircraft public water systems. In the interim, EPA placed 45 

air carriers under Administrative Orders on Consent (AOCs). Until the final ADWR 

compliance dates, air carriers remain subject to the existing national primary drinking water 

regulations or their respective AOCs. 

Who is affected by this rule? 

Aircraft which convey passengers in interstate commerce and are public water systems that board 

only finished water will be affected by this final ADWR. Aircraft that do not provide water for 

human consumption or those with water systems that do not regularly serve an average of at least 

twenty-five individuals daily do not meet the definition of a PWS. The final ADWR only addresses 

aircraft within U.S. jurisdiction; however, EPA supported an international effort led by the World 

Health Organization to develop international guidelines for aircraft drinking water. 

The ADWR applies to the aircraft’s onboard water system only. The components include: water 

service panel, storage tanks, pipes, valves, treatment devices, and plumbing fixtures within the 

aircraft that supply water to passengers or crew. The Food and Drug Administration (FDA) is 

responsible for regulating the watering points that include the water cabinets, carts, trucks, and hoses 

FACT SHEET: FINAL AIRCRAFT 

DRINKING WATER RULE 
Office of Water (4606) EPA 816-F-09-011 October 2009 2

from which aircraft board water. EPA and the states are responsible for regulating the public water 

systems that supply drinking water to the airport watering points. 

How much will the ADWR cost air carriers and consumers? 

EPA assumes that air carriers will pass on some or all of the costs of a new regulation to their 

passengers in the form of ticket price increases. EPA estimates that 708.4 million passengers 

travel each year on aircraft that are affected by the ADWR. EPA estimates air carriers’ total 

annualized cost to implement the ADWR to be about $6.95 million using a 7 percent discount 

rate. The cost passed on to passengers can be roughly estimated by dividing the air carriers’ 

annualized costs incurred by the number of passengers traveling each year. Based on this 

approximation, EPA estimates that passengers could face a relatively negligible increase of 

about one cent per ticket. 

What does the final rule require? 

The rule combines coliform sampling, best management practices, corrective action, public 

notification, operator training, and reporting and recordkeeping to improve public health 

protection. EPA believes that this rule provides the flexibility to meet the ever changing 

needs of the air carrier industry while still providing adequate barriers of protection. 

What is the frequency required for coliform sampling? 

The frequency of coliform monitoring is tied to the frequency of disinfection and flushing of 

the aircraft water system, as follows: 

Routine Disinfection and Flushing and Routine Sample Frequencies 

Minimum Routine Disinfection & Flushing 

Per Aircraft 

Minimum Frequency of Routine Samples Per 

Aircraft 

At least 4 times per year = At least once within 

every three-month period (quarterly) 

At least 1 time per year = At least once within 

every twelve-month period (annually) 

At least 3 times per year = At least once within 

every four-month period 

At least 2 times per year = At least once within 

every six-month period (semi-annually) 

At least 2 times per year = At least once within 

every six-month period (semi-annually) 

At least 4 times per year = At least once within 

every three-month period (quarterly) 

At least 1 time per year or less = At least once 

within every twelve-month period (annually)or 

less 

At least 12 times per year = At least once every 

month (monthly) 

Two coliform samples are taken per monitoring period: One sample must be taken from a 

lavatory and one sample from a galley. Any total coliform-positive sample must be further 

analyzed for the presence of E. coli. The air carrier must conduct disinfection and flushing of 

the aircraft water system in accordance with, or consistent with, the water system 

manufacturer’s recommendations. This allows for equipment-specific designs and for flexible 

implementation with the evolution of technology. In cases where a recommended routine 

disinfection and flushing frequency is not specified by the aircraft water system manufacturer, 

the air carrier is given the flexibility to choose a disinfection and flushing frequency, and 

corresponding monitoring frequency, specified in the above table. 
Office of Water (4606) EPA 816-F-09-011 October 2009 

What triggers corrective action and public notification?

Initial Corrective Action and Public Notification Requirements for Aircraft Wa

*Additional corrective actions based on repeat sample results or follow-up sample results are not reflected in this table.

Monitoring Result or Failure Corrective Action Public 

If any routine sample is total coliformpositive and E. coli-negative -- Perform disinfection and flushing no later than 72 hours after being notified by 

lab of total coliform-positive result, and collect follow-up samples; or -- Restrict public access to the water system no later than 72 hours after being notified by lab of total coliform-positive result; all public access restrictions must remain in-place until the aircraft water system has been disinfected and flushed and a complete set of follow-up samples has been collected; or -- Collect 3 repeat monitoring samples no later than 24 hours after being notified by lab of total coliform-positive result. 

If the air carrier chaccess to the watemust initiate publitime (i.e., no later being notified by positive result) anaircraft water systunrestricted publi
Office of Water (4606) EPA 816-F-09-011 October 2009 

Initial Corrective Action and Public Notification Requirements for Aircraft Wa

*Additional corrective actions based on repeat sample results or follow-up sample results are not reflected in this table.

Monitoring Result or Failure Corrective Action Public 

If any routine sample is E. coli-positive -- Restrict public access to the water 

system no later than 24 hours after being notified by lab of E. coli-positive result; 

all public access restrictions must remain in-place until the aircraft water system has been disinfected and flushed and a complete set of follow-up samples is total coliform-negative; and -- If the aircraft water system cannot be physically disconnected or shut-off, or the flow of water otherwise prevented through the tap(s), the air carrier must disinfect and flush the system no later than 72 hours after the lab notifies the air carrier of the E. coli-positive result; 

and -- Collect follow-up samples. 

Initiate public notrestriction of publ(i.e., no later than notified by lab of and continue until follow-up samplenegative. At that system may be retpublic access. 

Failure to perform routine disinfection and flushing or failure to collect and analyze the required routine coliform samples 

Restrict public access to the water system no later than 72 hours after discovery of the failure; all public access restrictions must remain in-place until the aircraft water system has been disinfected and flushed and a complete set of follow-up samples has been collected. 

Initiate public notrestriction of publ(i.e., no later than of the failure) and aircraft water systunrestricted publi
Office of Water (4606) EPA 816-F-09-011 October 2009 

Initial Corrective Action and Public Notification Requirements for Aircraft Wa

*Additional corrective actions based on repeat sample results or follow-up sample results are not reflected in this table.

Monitoring Result or Failure Corrective Action Public 

Failure to collect and analyze the required follow-up samples as a result of an E. coli-positive result 

-- Restrict public access to the water system no later than 24 hours after discovery of the failure; all public access restrictions must remain in-place until the aircraft water system has been disinfected and flushed and a complete set of followup samples is total coliform-negative; and -- If the aircraft water system cannot be physically disconnected or shut-off, or the flow of water otherwise prevented through the tap(s), the air carrier must disinfect and flush the system no later than 72 hours after the lab notifies the air carrier of the E. coli-positive result; and -- Collect follow-up samples. 

Initiate public notrestriction of publ(i.e., no later than of the failure) and complete set of focoliform-negativeaircraft water systunrestricted publi

Failure to collect and analyze the required repeat or follow-up samples as a result of a total coliform-positive and E. colinegative result 

Restrict public access to the water system no later than 72 hours after discovery of the failure; all public access restrictions must remain in-place until the aircraft water system has been disinfected and flushed and a complete set of follow-up samples has been collected. 

Initiate public notrestriction of publ(i.e., no later than of the failure) and aircraft water systunrestricted publi
Office of Water (4606) EPA 816-F-09-011 October 2009 

Initial Corrective Action and Public Notification Requirements for Aircraft Wa

*Additional corrective actions based on repeat sample results or follow-up sample results are not reflected in this table.

Monitoring Result or Failure Corrective Action Public 

When the air carrier becomes aware of an E. coli-positive event resulting from: (1) boarding water from a watering point not in accordance with FDA regulations (21 CFR part 1240 subpart E), or (2) boarding water that does not meet NPDWRs applicable to transient noncommunity water systems (§§141.62 and 141.63, as applied to TNCWS), or (3) boarding water that is otherwise determined to be unsafe due to noncompliance with the procedures specified in §141.804(b)(6). 

-- Restrict public access to the water system no later than 24 hours after discovery of the failure; all public access restrictions must remain in-place until the aircraft water system has been disinfected and flushed and a complete set of followup samples is total coliform-negative; and -- If the aircraft water system cannot be physically disconnected or shut-off, or the flow of water otherwise prevented through the tap(s), the air carrier must disinfect and flush the system no later than 72 hours after the lab notifies the air carrier of the E. coli-positive result; and -- Collect follow-up samples. 

Initiate public notrestriction of publ(i.e., no later than of the failure) and complete set of focoliform-negativeaircraft water systunrestricted publi
Office of Water (4606) EPA 816-F-09-011 October 2009 

Initial Corrective Action and Public Notification Requirements for Aircraft Wa

*Additional corrective actions based on repeat sample results or follow-up sample results are not reflected in this table.

Monitoring Result or Failure Corrective Action Public 

When the air carrier becomes aware of a non-E. coli-positive event resulting from: 

(1) boarding water from a watering point not in accordance with FDA regulations (21 CFR part 1240 subpart E), or (2) boarding water that does not meet NPDWRs applicable to transient noncommunity water systems (§§141.62 and 141.63, as applied to TNCWS), or (3) boarding water that is otherwise determined to be unsafe due to noncompliance with the procedures specified in §141.804(b)(6). 

Restrict public access to the water system no later than 72 hours after discovery of the failure; all public access restrictions must remain in-place until the aircraft water system has been disinfected and flushed and a complete set of follow-up samples has been collected. 

Initiate public notrestriction of publ(i.e., no later than of the failure) and aircraft water systunrestricted publi
Office of Water (4606) EPA 816-F-09-011 October 2009 8

What coliform sampling plans and operations and maintenance plans need to be 

developed? 

Each air carrier, for each aircraft that it owns or operates, must have a coliform sampling plan 

and an aircraft water system operation and maintenance plan within 18 months after the final 

rule is published for each existing aircraft public water system, and within the first calendar 

quarter of initial operation for new aircraft PWS. These plans must be included in a Federal 

Aviation Administration-accepted aircraft operations and maintenance program. The 

frequency for routine coliform sampling and routine disinfection and flushing must also be 

reported to EPA. 

What types of inspections or audits are required by the ADWR? 

Each air carrier must conduct a self-inspection of each aircraft water system no less frequently 

than once every 5 calendar years. In addition, EPA may conduct compliance audits as deemed 

necessary. The air carrier must address significant deficiencies found as a result of routine 

compliance audits or self-inspections within 90 days of identification of the deficiency, or 

where such deficiency is identified during extended or heavy maintenance, before the aircraft 

is put back into service. 

How will information (inventory data, sampling data, etc) be transmitted to EPA? 

As the primacy agency, EPA has oversight responsibility for aircraft PWS reporting 

information. To facilitate collection and analysis of aircraft PWS data, EPA is developing an 

internet-based electronic data collection and management system. This approach is similar to 

that used under the EPA SDWIS/STATE (Safe Drinking Water Information System/State 

version) reporting program. This is intended to reduce the reporting errors and limit the time 

involved in investigating, checking, and correcting errors at all levels. If an air carrier 

determines that it or its laboratory does not have the capability to report data electronically, 

the air carrier can submit a request to EPA to use an alternate reporting format. Regardless of 

the reporting process used, air carriers are to report the required information based on the 

schedule as stipulated in the ADWR. 

What are the compliance dates for the ADWR? 

Each air carrier must report a complete inventory of existing aircraft by 18 months following 

publication of the ADWR. In addition, the air carrier must report that it has developed a 

coliform sampling plan and an operations and maintenance plan that cover each existing 

aircraft. Air carriers must comply with all remaining requirements (e.g., routine disinfection 

and flushing, routine sampling) beginning 24 months following publication of the ADWR. 

How can I get more information? 

EPA’s ADWR and other supporting information are available on EPA’s Web site at 

http://www.epa.gov/safewater/airlinewater/index.html. For additional information about the 

final rule, contact the Safe Drinking Water Hotline toll free Monday through Friday, 10:00 am 

to 4:00 pm eastern time (except Federal holidays) at 1-800-426-4791.